Steam-engine valve-gear.



W. S. BROWN.

STEAM ENGINE VALVE GEAR.

APPLICATION FILED MAY 12, 191s.

Patented Feb. 3, 1914.

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few 57@ WITNESSES W. S. BROWN.

STEAM ENGINE VALVE GEAR.

APPLIUATION FILED MAY 12, 1913. v

'Patented Feb. 3, 1914.

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WILLIAM SHERMAN BROWN, 0F KNOXVILLE, TENNESSEE.

STEAM-ENGINE VALVE-GEAR.

To all whom it may concern.'

Be it kno-wn that I, WILLIAM SHERMAN BRowN, a citizen of the United States, residing at Knoxville, in the county of Knox and State of Tennessee, have invented a new and useful Improvement in Steam-Engine Valve-Gear, of which the following is a specification, reference being had to the accompanying drawing. y

My improvement relates particularly to mechanism for transmitting motion from the crank of a drive wheel of a steam locomotive to the distributing valve which admits steam to the cylinder.

The object of the improvement is to provide a construction which is simple, has the parts accessibly located, and avoids irregularity of valve action due to lost motion or pounding at the crank.

This improvement is a modilication of the mechanism described by my United States patent No. 1,033,532, granted July 23, 1912, for Steam-engine valve-gear.

In the accompanying drawings, Figure 1 is a side elevation, portions being broken away, showing my improvement applied to one side of a locomotive; Fig. 2 is a plan of a portion of the mechanism shown by Fig. 1; Fig. 3 is a section on the line, 3-3, of Fig. 2, looking toward the right; Fig. 4 is a section on the line, 4 4, of Fig. 2, looking in the direction of the arrow; Fig. 5 is a plan of a bracket on which the bell crank is supported; Fig. 6 is a side elevation of said bracket; Fig. 7 is a section on the line, 7 7, of Fig. 1, looking toward the left; Fig. 8 is an elevation of a combined bearing and standard; Fig. 9 is a side elevation similar to Fig. 1, illustrating a modification; Fig. 10 is a section on the line, 10-10, of Fig. 9, looking toward the left.

Referring tosaid drawings, 1, is the usual valve stem extending to the distributing valve (not shown). The usual horizontal, parallel cross-head guide bars, 2, are supported at their rear ends by the guide yoke extension, 3. The usual connecting rod or pitman, 4, is coupled to the usual main crank, 5, carried by a drive wheel, D. On the main crank, 5, is rigidly mounted an eeendiee 90 elesfeee .ferward of the main crank. To said wailfxilniamry crank is coupled one end of Vpitgrnan rodm A bridge, B, is located ""lveftliieifraiie, A, and extends from the ordinary guide-yoke, 8, and guide-yoke ex- Specication of Letters Patent.

Application filed May 12, 1913.

Patented Feb. 3,1914. serial No. 767,230.

tension, 3, to the cross beam or plate, 10, and is secured to said guide-yoke and to said crosswbeam by means of bolts, 9. Said bridge is in the form of a plate having its length horizontal and being turned to bring its long edges into an upright plane. At its rear end, the bridge has a lateral extension, l1, resting against the cross-beam, 10, and receiving said bolts, 9. At its forward end the bridge has a transverse extension, 12, reaching to both sides of the body of the bridge and resting against the guide yoke, 8, and the guide yoke extension, 3, and receiving said bolts, 9. The innermost of said bolts extend through the transverse extension, 12, and the guide yoke, 8, while the others of said bolts extend through said member and through the guide yoke, 8, and the guide yoke extension 3. On the outer portion of the transverse member, 12, and integral therewith is an ear, 13, which is directed rearward; and on the inner portion of said transverse member is another ear, 14, also directed rearward and located horizontally opposite the ear, 13. Each of said ears has a. bearing, 15, receiving the ends of a shaft, 16. On said shaft is a bell crank or rocking member, F, preferably rotatable on said shaft, the latter being held immovably in its bearings. Said bell crank has two approximately horizontal arms, 17, and a depending arm, 18. The lat-ter arm is coupled to the valve-stem, 1. By rocking the bell crank, the valve-stem is reciprocated.

An approximately upright link, 19, has its upper end coupled to the arms, 17, of the bell crank, while its lower end is coupled to the forward end of the auxiliary pitman rod, 7, both ends of said link being forked to receive said rod and said arms, as shown in the drawings. Said arms, 17, are also forked to receive the upper ends of the link, 19. Rearward of said bell crank the bridge has a lateral extension, C. On this portion of the bridge is seated a bearing box, E, secured to the bridge by bolts, 20. Said box receives a short rock-shaft, 21, which is horizontal and transverse to the frame. On

the outer end of said shaft, 21, is a rocking arm, 22, directed downward and having at its upper end a horizontal wrist, 23. An approximately upright oscillatory arc lever, 24, has a transverse bearing, 25, between its ends, and the wrist, 23, extends through said bearing for supporting said lever. A U-shape bracket, 26, has one arm bolted to the bridge and in its other arm is an upright slot, 27, extending through said standard from the outer to the inner side thereof. In said slot, is a slide-block, 2S. A bolt, 29, extends through the lower end of the arc lever, 24, and through said slideblock, it` being loose for rotation in said lever or said block, whereby the lower end of said lever is held for up and down reciprocation and for oscillation of its upper por` tion on the axis of the bolt, 29. If the bolt, 29, and the slide-block, 28, were stationary during the oscillation of said arc lever, the path traversed by the bolt, 31, in the upper end of the arc lever, would be concentric to the axis of the bolt, 29. But such path is modified by the bodily rising of the arc lever during its'A movement away from the upright plane in which lies the axis of the rock shaft, 21, as will hereinafter appear. To the upper end of the arc lever is coupled the upper end of an approximately upright link, 30, by means of a bolt, 31, the upper end of said link being made U-form to receive the upper end of the arc lever. The lower end of said link is coupled to the auxiliary pitman rod, 7, by means of a bolt, 32, in the upright plane in which the axis of the rocking shaft, 21, lies, the location for said bolt being taken when the lauxiliary crank is on either the upper or the lower quarter.

As above stated, during each oscillation, the path of the bolt, 31, is modified by the bodily upward movement of the arc lever as it moves toward each extreme of its oscillation. This modification involves an inversion of the curves so that said path becomes concentric to an axis below said path. The height of said axis may be varied by varying the relative proportions of the rocking arm, 22, the arc lever, 24, and the link, 30. For best results, said axis is to be made coincident with the lower axis of the link, 30, (which is the axis of the bolt, 32), when the lower end of said link is at the middle of its path of oscillation, which middle is, as above stated, in the upright plane in which the axis of the rock shaft, 21, lies.

The forward end of an auxiliary reach rod, 33, is coupled to the arc lever, 24, by means of the bolt, 31, said rod lying beside the upper end of the arc lever within the U of the link, e0. The rear end of said auxiliary reach rod is coupled to the upright arm, 34, which is rigid on the rock shaft, 35, which shaft is supported in bearings, 36. On said rock shaft, is an arm, 37, to which is coupled a rod, 3S, which is in turn coupled to the ordinary reversing lever, 39, working on a sector or quadrant, 40.

In operation, the arc lever is set to bring its upper end into any desired position in its`curved path, this being done by means of the reversing lever; and while said aro lever is so set, the link, 30, oscillates on the upper end of said arc lever (on the axis of the bolt, 31,) during each reciprocation of the auxiliary pitman rod, the axis of the bolt, 32, moving in an arc in which lies the axis to which the path of the lower end of the arc lever, or of the bolt, 31, is concentric. And, as above indicated, the distance between the wrist of the auxiliary crank, 6, and the bolt, 32, is such as to bring the axis of said bolt into the axis of the arc path of the lower end of the arc lever when said crank is on the upper or the lower quarter, at which time the main crank is on either the front or the rear quarter. 1n Fig. l, it is shown on the front quarter, the auxiliary crank being on the top quarter. During each such reciprocation, said auxiliary pitman rod rocks bodily with the axis of the bolt, 32, as a fulcrum. This involves the rising and falling of the forward end of said auxiliary rod, and during such movement of said end of said rod, the link, 17, is forced up and down, and such movement of said link causes the rocking of the bell crank, F, and the reciprocation of the valve stem, 1.

The gear is reversed by throwing the reversing lever across the center in the usual manner, and the opening of the valve is varied by moving the lower end of the arc lever nearer to and farther from the plane in which the axis of the rock shaft, 21, lies, this being accomplished by the aid of suitable notches (not shown) on the reversing lever sector. When the lower end of the arc lever is on the middle of its path (or in said upright plane), the valve motion is reduced to the extent of the lead.

In the form illustrated by Figs. 9 and 10, the rock-shaft, 35, bearings, 35, arm 34, and auxiliary reach rod, 33, are omitted, and a longer rock shaft, 41, is substituted for the rock shaft, 21., of Fig. 7, and the reach arm, 42, corresponding,` to the arm, 37, on the rock shaft., 35, is placed on the shaft, 41, and its upper end coupled to the forward end of the reach rod, 38. T ie rocking arm, 22, is placed upon the outer end of the shaft, 41, the same as said arm is placed on the shaft, 21, in Fig. 7.

The drawings have heen copied, in part, from larger working drawings used in applying my improvement to a railway freight locomotive having a piston stroke of 30 inches and having a minimum valve travel of 54j inches and a lead of three sixteenths of an inch. The radius of the auxiliary crank, 6, (measuring from the driver axis) is 8 and inches. The distance from the auxiliary crank along the auxiliary pitman rod, 7, to the axis of the bolt, 32, is 74 and 3/32 inches. From the latter point on said pitman rod to the link, 17, is 1() and 13/32 inches. The length of the link, 30, is 35 and 11/16 inches, and that, as already described, is also the radius of the curved path of the bolt, 31, which carries the upper end of the link, 30; and the center of said curved path coincides with the axis of the bolt, 33, when the auxiliary crank is on the upper quarter or the lower quarter, at which time said bolt isone and'five sixteenth inches below the level of the driver axis and the cylinder axis (the working line or center line of motion The length of the link, 17, is 32 inches. The height of the axis or fulcrum of the bell crank or rocking` member, C, above the level of the center line of motion is 32 and Q/S inches. The length of the arms, 15 and 16, of the bell crank is 12 and inches. The rocking member, C, as used on said engine, is not a true bell crank, its angle being less than ninety degrees-72 degrees.

When the engine is in forward motion and the main crank is on the back center and the auxiliary crank on the upper quarter, the arm, 15, is 2 and .1E degrees back of a vertical line cutting the fulcrum, and the arc, 15, is 15 and degrees below a horizontal line cutting the fulcrum. When the arc lever is set for full valve travel and inches), the forward travel of the arm, 16, from the positie-n mentioned is 7 and degrees and the back travel of said arm from said position of 19 degrees, and the arm, 15, travel downward and upward correspondingly. Thus the larger portion of the travel of the rocking member arms is within the 90 degree angle formed by said vertical and said horizontal lines. These relative proportions and positions of the various parts of the mechanism produce the desired quick movement of the valve during the opening and closing and also produce equalized travel of the valve over the port during the forward motion and during the backward motion.

It is to be observed that my improvement eliminates from the valve mechanism the eccentric and also all parts having a high velocity. No part of the valve mechanism is connected to the connecting rod nor the cross-head. Movement is transmitted to the valve stem from the wrist of the auxiliary crank and said wrist travels in a relatively small `circle.- Thus the. movement of the auxiliary rod and the links, 17, and 30, are through relatively short ranges. Furthermore, it is to be noted that lost motion due to wear at the wrist of the auxiliary crank will chiefly modify the lengthwise movement of the auxiliary pitman, 7, while the movement transmitted through the link, 17, is approximately at right angles to said auxiliary pitman. Hence the modification of the longitudinal movement of said pitman is substantially not transmitted to said link. And it will be seen that such modification of the rocking movement of the auxiliary pitman due to wear at the wrist of the auxiliary crank will affect the link, 17, in minimized form, because the portion of the auxiliary pitman lbetween the axis, 3:2, and the link, 17, is much less than between said axis and the wrist of the auxiliary crank. In this connectie-n it is to be reinembered that wear by the auxiliary crank wrist in the auxiliary pitman is chiefly in the direction of the length of said pitman. Such wear produces wiat is termed lost motion or pounding at the crank.

I claim as my invention:

1. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reciproca-tory arc leverfcoupled between its ends to the lower end of said rocking member, means for guiding the lower end of said arc lever for approximately upright reciprocation, an auxiliary cranl ,l a`nw auxiliarywrmod coupled to said crank, and twoalppioximately upright linlrffe'ach having its lower end coupled to the anxiliaryrod and ondhaving its upper enducouple'dnto the upper end of the arc lever and the other having its upper end in operative relation with the distributing valve stem, substantially as described.

2. lIn a steam engine valve gear, the combination of a rocking member extending` downward from its bearing, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, means forming an upright slideway connection for the lower end of said are lever, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the arc lever and the other having its upper end in operative relation with the distributing valve stem, substantially as described.

3. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, an upright, reciprocatory are lever coupled between its ends to the lower end of said rocking member, means for guiding the lower end of said arc lever for approximately upright reciprocation, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and the rear of said links having its upper end coupiled to the upper end of the arc lever and the other link having its upper end in operative relation with the distributing valve stem, substantially as described.

4l. In a steam engine valve gear, the com- Cil bination of a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end oi said rocking member, means forming an upright slideway connection for the lower end of said arc lever, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and the rear oi| said links having` its upper end coupled to the upper end ot the arc lever and the other link having its Vupper end in operative relation with the distributing valve stem, substantially as described.

5. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, lneans for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, a fixed standard in operative relation with the lower end ot' said arc lever tor limiting said end to upright movement, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and one having` its upper end coupled to the upper end of the are lever and the other having` its upper end in operative relation with the distributing valve stem, substantially as described.

G. In a steam engine valve gear, the combination of a rocking member extendingl downward from its bearing, means for rocking said rocking` member, an upright, reciprocatory are lever coupled between its ends to the lower end of said rocking member, a fixed standard in operative relation with the lower end of said are lever for limiting said end to upright movement, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the are lever and the other having its upper end in operative relation with the distributing valve stem, substantially as described.

7. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, a fixed standard in operative relation with the lower end of said arc lever for limiting said end to upright movement, an auxiliary crank, an auxiliary rod coupled to said crank, and two approxiniately upright links, each having its lower end coupled to the auxiliary rod and the rcar of said links having its upper end coupled to the upper end ot' the arc lever and the other link having its upper end in operative relation wit-h the distributing valve stem, substantially as described.

S. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends tothe lower end of said rockingl member, a iixed standard in operative relation with the lower end of said arc lever for limiting said ends to upright movement, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and the rear of said links having its upper end coupled to the upper end of the are lever and the other link having its upper end in operative relation with the distributing valve stem, Substantially as describ-ed.

9. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, means for rocking said rocking` member, an upright, reciprocatory are lever coupled between ends to the lower end of said rocking member, means for guiding one end of said arc lever for approximately upright reciprocation, an auxiliary crank, an auxiliary rod coupled to said crank, two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the are lever, and a bell crank coupled to the upper end of the other of said links and connected in operative relation with the distributing' valve st-em, substantially as described.

l0. In a steam engine valve gear, the combination oi a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end ot said rocking member, means Jforming an upright slide way connection for the lower end of said are lever, an auxiliary crank, an auxiliary rod coupled to said crank, two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the oscillatory end ot' the arc lever, and a bell crank coupled to the upper end of the other of said links and connected in operative relation with the distributing valve stem, substantially as described.

ll. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, an upright, reciprecaiory arc lever coupled between its ends to the lower end of said ro-cking member, means for grueling the lower end of said arc lever for approximately upright reciprocation, an auxiliary crank, an auxiliary rod coupled to said crank, two approximately upright links, each havingits lower llO Cab

end coupled to the auxiliary rod and one having its upper end coupled to the upper end cit' the arc lever, and a bell crank coupled to the upper end of the other of said links and connected in operative relation with the distributing valve stem, substantially as described.

12. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reoiprtcatory arc lever coupled between its ends to the upper end ot' said rocking member, means forming an upright slideway connection for the upper end of said arc lever, an auxiliary crank, an auxiliary rod coupled to said crank, two appro-ximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the lower end of the arc lever, and a bell crank coupled to the upper end of the other of said links and connected in operative relation with the distributing valve stem, substantially as described.

13. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, a fixed standard in operative relation with the lower end of said arc lever for limiting said end to upright movement, an auxiliary crank, an auxiliary rod coupled to said crank, two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end ot' the arc lever, and a bell crank coupled to the upper end of the other of said links and connected in operative relation with the distributing valve stem, substantially as described.

14. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, a fixed standard in operative relation with the lower end of said arc lever for limiting said end to upright movement, an auxiliary crank, an auxiliary rod coupled to said crank, two approximately upright links, each having its .lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the arc lever, and a bell crank coupled to the upper end of the other of said links and connected in operative relation with the distributing valve stem, substantially as described.

15. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, a fixed standard in operative relation with the lower end of said arc lever for limiting said end to upright movement, an auxiliary crank, an-auxiliary rod coupled to said crank, two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the are lever, and a bell crank coupled to t-he upper end of the other of said links and connected in operative relation with the distributing valve stem, substantially as described.

16. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reciprocatory arc level' coupled between its ends to the lower end of said rocking member, a ixed standard in operative relation with the lower end of said arc lever for limit-ing said ends to upright movement, an auxiliary crank, an auxiliary rod coupled to said crank, two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the arc lever, and a bell crank coupled to the upper end of the other of said links and connected in operative relation with the distributing valve stem, substantially as described.

17. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, a fixed standard in operative relation with the lower end of said arc lever for limiting said end to upright movement, an auxiliary crank, an auxiliary rod coupled to said crank, two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the arc lever, and a bell crank coupled to the upper end of the other of said links and connected in operative relation with the distributing valve stem, substantially as described.

1S. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, a reversing lever, a reversing shaft in operative relation with said reversing lever and with said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, means for guiding the lower end of said arc lever for approximately upright reeiprocation, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the are lever and the other having its upper end in operative relation with the distributing valve stem, substantially as described.

19. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, a reversing lever, a reversing shaft in operative relation with said reversing lever and with said rocking member, an upright, reciprocatory arc lever' coupled between its ends to the lower end ot said rocking member, means forming an upright slide way connection for the lower end of said arc lever, an auxiliary c ank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end of the arc lever and the other having its upper end in operative relation with the distributing valve stem` substantially as described.

20. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, a reversing lever, a reversing shaft in operative relation with said lever and with said rocking member, an upright, reciprocatory are lever cou pled between its ends to the lower end of said rocking member, means for guiding the lower end of said arc lever for approximately upright reciprocation, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and the rear of said links having its upper end coupled to the upper end of the are lever and the other link having its upper end in operative relation with the distributing valve stem, substantially as described.

2l. In a steam engine valve gear, the combination of a rocking member extending downward from its bearing, a reversing lever, a reversing shaft in operative relation with said reversing lever and with said rocking member, an upright, reciprocatory are lever coupled between its ends to the lower end of said rocking member, means forming an upright slide way connection for the lower end of said arc lever, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links,

each having its lower end coupled to the auxiliary' rod and the rear of said links having its4 upper end coupled to the upper end of the are lever and the other link having its upper end in operative relation with the distributing valve stem, substantially as described.

22. In a steam engine valve gear, the combination of a bridge on the engine frame, a rocking member supported by said bridge and extending downward from its axis, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, means for guiding the lower end of said arc lever for approximately upright reciprocation, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and one having its upper end coupled to the upper end oi? the are lever and the other having its upper end in operative relation with the distributing valve stem, substantially as described.

In a steam engine valve gear, the combination of a bridge on the engine frame, a bearing seated on said bridge, a rocking member seated in and extending downward from said bearing, means for rocking said rocking member, an upright, reciprocatory arc lever coupled between its ends to the lower end of said rocking member, means for guiding the lower end of said arc lever for approximately upright reciprocat-ion, an auxiliary crank, an auxiliary rod coupled to said crank, and two approximately upright links, each having its lower end coupled to the auxiliary rod and 011e having its upper end coupled to the upper endof the arc lever and the other having its upper end in operative relation with the distributing valve stem, substantially as described.

In testimony whereof I have signed my name, in presence of two witnesses, this 10th day ot' May, in the year one thousand nine hundred and thirteen.

IVILLIAM SHERMAN BROIVN. lVitnesses CYnUs KEER,

H. P. STRAYER.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents.

Washington, D. C. 

